Glass-drawing apparatus



GLSS DRAWING APPARATUS Filed Feb. 25. 17923 2 Shyoptl-'Sheei l1 FIEJL.'

ZMW

Qct. 13,v 1925'.

lH. G.vsLlNGl.uFF. y

GLASS DRAWING APPARATUS Filed Feb. 26, 1,923

FIE.Z.

' 5 drawing tank 2 is of considerable Patented oct. 13, 19251 UNITED STATES PATENT OFFICE.

HARRY G. SLINGLUFF,

OF MOUNT VERNON, OHIO, ASSIGNOR TO PXPIBUBGH PLFL GLASS COMPANY, A CORPORATIOMF FENNSYLVANI.

GLASS-DRAWING animamos.

Application mea rebmary as, 192s. serial no. 621,183.

rovement relates primarily to the guiding '15 ar located beneath the lilneof generation of the sheet and has for its rincipal objects the provision of a bar ten ing to produce a sheet of very uniform thickness from edge 'to edge and which is flat and .free from warping and strain. The edge portions of the sheet being exposed to a' greater extent to the chilling action of the atmosphere tend to draw thicker than the central portion which is exposed to a greater degreegto the heat from the molten glass beneath. The guiding bar .constituting vthe improvement of the present application tends to neutrallze thisl condition. The result -is accomplished by shaping the guiding bar as illustrated l0 in the accompanying drawings wherein:

Fiffure 1 is a-vertical section through the drawlng tank and the drawing apparatus located thereabove. Fig. 2 is a plan view of the improved form of bar. Figsfj and 4 Il are'sections on the lines, ITI-Ill and 1V* 1V o Fig. 2. Fig. 5 is a side elevation of the bar of Fig. 2. Figs. 6 and 7 are views illustrating a modification, Fig. 6 being a plan view and Fig. 7 a transverse section 'w on the une vii-vir 0f Fig. c. nig. e is a transverse section of another modified form of bar constructed similar to Fig. 6 but hav` in a guiding slot instead of the guiding ri ge' of the Figs. 6 and 7 construction. Referring .to the drawings, 1 is the melting tank, which may be of any approved form and which is provided with the usual regenerative heating means, and 2 is the drawing tank. As indicated in Fi 1, the epth, so

as to give a depth of lass, preferably ranghe width of the tank ing from 2 to 4 feet.

' widens out vertical edges .nace and in use the depends upon the width of the sheet which it is desired to draw, such width being, for instance 6 feet, where the width ,of the sheet to be drawn is 5 feet.

The drawing tank is capped with the arch 4 at the end. adjacent the melting tankl and with the block 5 adjacent the rear end of 1 the drawing tank. A pair of shielding mem- Abers 6 and 7, L shaped in cross section are provided on opposite sides of the sheet. Suitable burners 8 and 9 are provided in order to prevent the body of glassin the drawing tank from becomingchilledbelow the proper drawing temperature. Slrimming bars 11 are employed and intermediate these bars and between 'the shielding members 6 and 7 is located the guiding bar 10 to'which the present improvement particularly rev lates; v

The sheet may be drawn by any desired type of drawing mcchanisrn,'althong;h the type illustrated in my Patent No. 1,364,865 is preferred, such typeof apparatusbeing illustrated diagrainmatically in Fig. 1 of the present application. This apparatus in'its simplest form comprises a pair ot' endless belts 12 of asbestos carried by pulleys 18 and 14 driven by suitable mechanism. not shown. This belt apparatus prevents the glass from cooling too rapidly and after passing the upper pulleys 13, it is cut oil' by any suitable means. Asbestos rolls 15 and 16 may also be used intermediate the bath and the "1P-estos curtains in order to assist in heidi sheet straight, and such rolls may i driven by means, not shown, in order t assist in drawing the sheet.

The construction of the guiding il) is 'shown `in detail in Figs. '2, 6 and f4. At the center the bar is rectangular in cross section and is provided with the vertical slot 17. decreasing in width from the lower side of the bar upward. At the ends of the bar this slot as indicated at 18, such widened portion beingr designed to lie beneath the of the sheetbeing drawn. The end portions 19 of 'the bar are fitted into suitable recesses in the side walls of the -furbar is held submerged as indicated in Fig. 1, preferably withits upper face from 3 to 4 inches below the surface of the glass, From the central perl.

.ifnlilially tbe saine w dtli :is but at top is only about width at tbe bottoni. rlliis con4 i bar has been found to rive a A `rli is more uniform in thickness tl'io center to the edges than is tlie case '-.vncre a bar is need wliicli the sanie cross t i :from end to end. lilith snob i bar nov five life portions in the odiiced 'einen .ie slightly thicker central `portion. The relatively ic bar at the center than at 1, to give a slightly greater ng eilcct to the central portions or the sh and tlins correct the tendency ci' tbe to tliin slightly at the center.

This result may be secured by inodiied t pes ot bar construction, tonic ot which are i'4 fied. although that og'r' Figs. 2, 3 and fred. Figs. G and 7 illustrate a torni bei* in wint-l1 tile -guide slot l? of Fig. 2 cont tion is omni l and place thereof, i e 2l is employed for lfeeping tbe line 'ation oi' the sheet straight and in i over tlie center line ci tire bar. rThis idg/:rofl

lo tbe end portions ln lziori. however., there is le.. ci.' tlie bar inward "toni up the case in the fyction of lilies. 27 3 and 4l as indicated at Qil. The constincl'ion of Figs. 6 and 7 may be further modified by omitting' tbe guide ridge 2l and substituting therefor tbe guide slot 24k as indicated in Fin'.- 8, Fig. S beine desiened to illustrate tbe cross section ci z similar throughout to that ot Figs. tl and 6 except that tli slotted. in all eese types ci i .endency is to n iin tlic sheet traiglit directly above renter line et the bar and to reduce the teinlency of tlie sheet to draw thicker at tbe fre portions than in the center and the invention contemplates broadly the increasing oi" tbe chilling eil'ect or the bar by varying its mass or ai.rane;ement of material from the ingle-e portions to the central portion.

llie horizontal of tlic shields 6 and if serve as supports for refractory shade )lates Q5 ci F l.. These plates, when in ase. as illustrated, serve to intensify the lieat in tbe bath or on the base of tlie sheet lying.r below or opposite7 since the heal trom the bath is reflected baclr :from tbe over hanging edges ci the plates. W'lien not in use, the plates are pushed back so that they. do not project out past the vertical edges ot the shields. ln case tile slieet of glia/ssV at its base becomes unduly thickenedl atL certain point in its widtli or develops any imper- 1:1". at sucia which can be reduced n cross section troni the cen-v by an increased temperature. the. shade plate moved ont over or opposite sach point1 .nus securing the desired increase in temperture number oi' plates may be used at iii' nt points at tbe saine time, if desired.

v"Ji/bat l claim is: l. ln combination in apparatus for dravingf slice( glassT a `lass drawiin;` tank adapted zo carry a bath of molten glass, at a particular level. means for drawing` a sheet upward from tile bath and a refractory bar in the batb and extending; transversely across tbe tank below said level of the bath and the line ot generation ot the slieet, said bar having' its upper portion oi varying width, wid at the center portion and decreasing dtli toward the end portion.

2. ln combination in apparatus for drawing sheet glass, a glass drawing tank adapted to carry a bath ci: molten glass at a. particular level, .means for drawing a sheet upward from the bath and a refractory vertically slotted bar in the bath and extending' transversely across tlie ytank below said level of the bath and the line of generation of the sheet, said bar having its upper portion of varying width, widest at the center portion and decreasing in width toward the end portion.

3. ln combination in apparatus for drawing' sheet glass, a glass drawing tank adapted to carry a. bath of molten glass at a particular level, means for drawing a sheet upward 'from the) bath and arefractory bar in the bath an'd extending transversely across the tank below said level of the path and tlie line of generation of the sheet, said bar having its upper portion beveled away trom the ends outward from the center in such manner that vtine upper face of the bar ot decreasing width from the center por tion to the end portions.

'ing sheet glass, a glass drawing tank adapted to carry a bath of molten glass at a particular level, means for drawing a sheet upward from the bath and a refractory bar in the bath and extending transversely across the tank below scid level of the path and tbe line or' generation of tile sheet, said bar decreasing in vertical cross section from its center portieri to its end. port? ms.

5. in combination in apparatus for drawing sheet glass, a glass drawing tank adapted to carry a bath of molten glass at a. particular level, means for drawing a sheet upward from the bath and a refractory bar in the batband extending transversely ac oss the tank below said level of the bath and tbe line of generation of the sheet, said bar having sheet guiding means extending longitudinally of tbe. bar and decreasing in vertical cross section from its center portion to its end portions.

6. In combination in apparatus for time 4. in combination in apparatus for draw# i in'g sheet glass, a' glass drawing tank 'to bei-positioned Wit-h theedges thereof overadapted to carry a bat of molten glass at a hanging the edges of said lateral flanges. particular level. mean for drawing a sheet In testimony whereofI have hereunto sub- 10 upw'ardfrom the bath, a pair of shielding scribed my-name this 29th day of Jany., blocks lying 'on opposite'sides of the sheet', 1923.

and having lateral flanges or ledges, and refractory shade means on the ledges free. HARRY G. SLINGLUFF. 

